Sonorous Hum + Call Lightning?

[Yorae]

Does this work?

Call lightning says "each round after the first you may use a standard action (concentrating on the spell) to call a bolt". Could a caster use Sonorous Hum to concentrate on this and call the lightning bolts for them?

[The Boz]

Won't work, calling lightning is a standard action, and the part in the brackets is just a descriptor.

[Keld Denar]

Calling Lightning isn't "concentrating", its...something else. For an example of what "concentrating" is, consult something like Silent Image or Detect Magic.